Jamaal Charles knows he is underpaid and is willing to sit out until his contract is remedied.

NFL Media Insider Ian Rapoport reported Wednesday morning that, barring a contract breakthrough, the running back will not report for Kansas City Chiefs training camp Wednesday, according to a source familiar with Charles' thinking.

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Charles signed a six-year, $27.97 million contract in 2010 but is due just $3.65 million in 2014 -- well below market value for a player who accounted for 35 percent of the Chiefs' offense in 2013.

The 27-year-old is coming off a 1,287 yards rushing season with 1,980 yards from scrimmage -- 2nd in the NFL -- and 19 total touchdowns. Charles has never averaged less than 5 yards per carry in a season and has proven to be one of the most dynamic players in the NFL.